Wire strapping tool



April 29, 1952 H. K. EMBREE WIRE .STRAPPING TOOL Filed July 11, 1946- MAZZ'or-neys Patented Apr. 29, 1952 Harold K. Embree, Hamilton, Ontario, Gamma.

assignor t'o Griplock, Inc., Hobcken, N. J acorilblati'on of Delaware Application .rul'y'n, 194s, serials-o. 82973 This invention relates to a 'wire strapping tool designed for tensionin'gand fastening around packages straps composed o'fwire or the like;

and it is particularly intended to be used in com"- bination and cooperation with a wire strap which has been formed withone end of the wireturned back and coiled around thebody of the wire .so that the knotor fastening maybe made bypassingthe-other end of the wire strap through the said coil and then crushing orflattening the coil so as to deform it and the parts of the'wire strap therewithin into a firm interlocking engagement. Simultaneously with this knotting of the strap, theexcessof its free end is severed, to improve the appearance of the result, and to eliminate the long end which might present a hazard'in subsequent handling and shipment.

The purpose of the invention is to provide certain novel and improved features in the structure and arrangement of the tool-shown inapplication for United States Patent filed by'Bur-ton L. Watt and myself .on February 3, 1945, Serial No.'5 '76,054, now Patent No. 2,442,679 dated June 1, 1948; which said tool was an improvement upon that shown in United States Patent of BurtonjL. Watt and James J. Smith, No. 2,124,991, issued July 26, 1938.

More particularly, the invention relates 'tothe tensioning function of the'tool, with the object of providing means whereby a predetermined tension will be-uniformly applied to successive straps regardless of the strength of or effort applied by the operator.

Another object is to provide means whiehwill enable the tension operatinglever -or the like, to be brought toits at rest position following the attainment .of the ..predetermined tension, without affecting .the tension and regardless of the position of the'lever at the moment.

Another object is-to provide means for adjusting-the parts which cooperate in producing the tension so that various degrees of tension may be fixed in accordance with the requirements relating to'thecharacteristics of the package, the

strength of the strap; shipping conditions, etc.

A 'furthero'bject is to provide certain improvements in the form, construction and arrangement of the parts whereby the above named and other objects-inherent inthe construction may be efiectively attained and the general efficiency of the tool increased.

Practical embodiments of the invention are shown inthe accompanying drawings, in which Fig. 1 represents a top plan view of the tool, partly'brokenaway; I b

Fig. 2 represents a side elevation of the tool, partly broken away, in association with the ends 2 bi thewire strap which are in seems-ven s tion preliminary to the step of tensiohi-n'g, knotting, and severing the surplus wire;

Fig. '3 represents an Jenlarged'd'etail section, partly in elevation, of the preferred form of slip drive mechanism for rendering the tensioning means ineffective after thpredetermined tension has been attained;

Fig. 4 represents a partly broken sectiontak'en in the planejof the line IV-;IV:of Fig. 3, looking in the direction'of tnearrows;

[Fig 5 represents 'a view similar to Fig. Sybilt showing a modified .'form of mechanism;

, Figfi'r'epresents' a view similar'toFig. '3, but showing T a second modified form of "mechanism; Fig. 7 represents "a detairside elevation, partly in section, of. a thirdimodifiedi'forin'ofmechanism for thes'ame purpose; I

Fig. 8 represents a view similar'to Fig. 7, with certain; parts shown in difierehtipositions; {and ciepresents a section taken in the lplaiie of'th e line IX-IXo'f Fig. '8, looking"inthedirec ti on of the arrows.

The tool which-constitutes'the Subjetfii'iatter of this invention is: bf that 'class designed for cooperative use with'wir straps sii'ch-asfhreinabove described,-in order rapidly andsecurely to bind packages which "may consi'stofa'group or pile of separate articles, '61 [a container "in by a crushing pressure to term the desired knot which fastens thestrapin its .tehsiohed.cohditicn, with simultaneous severing of 'the eiic'es's orsurplus end of the "strap. Thosevportions of the strap witnc'toseratewith and are acted pon by the tool are shownin Fig. '2, where the body of the strap -is de'noted by A; its coi-1'by- -B; andits end; which is (passed through the coil for .kriotting and subsequent severing of the excess, ismarkedC. It wiliflbe understood that the broken away part of the strap which is not seen in the figdreconsists "of themain body thereof which hJSibhbissd around the package before the ftool'has' been placed in operative position.

correspond with said patent and application in order to establish a background for detailed description of the present inventive features.

The tool comprises a base I which has inte grally formed therewith an uprising web 2 which forms a support for a head 3 that provides a housing and bearings for certain of the operative elements.

The gripping mechanism which seizes the body A of the wire at a point adjacent the coil B during the tensioning step, includes a serrated law 4 which is secured to the side of base I by screws such as 5, and cooperates with a movable jaw 6 which is arranged to be slid into and out of operative relationship with respect to the fixed jaw 4 by an arm I that is controlled by a hand lever I9, as is fully described in said Patent 2,124,991.

Relerring to the form of the invention shown in Figs. 1 to 4, a tensioning hub 21 is journaled in extensions 22 and 23 that are integral with and connect the base I and head 3; extension 22 serving as a direct bearing for the hub 2I, while extension 23 acts through a cup 24 which is fitted therein and has a central hole that embraces a stem 25 which is integral with and extends rearwardly from the hub 2 I. Teeth 46 project laterally from the face of hub 2I and are intended to receive between them the free end C of the wire strap, which latter also passes through a hook 3'! that is carried by the movable jaw and located intermediate the tensioning hub 21 and the point at which the knotting and severing of the strap takes place; said hook 31 serving the purpose of urging the strap into engagement with teeth 48 on hub 2 I.

A bored ratchet wheel is located adjacent to and in surface contact with hub 21, and is arranged to be actuated by a spring pawl 4! which is bolted to the hand lever I9, and to be held against opposite motion by a spring pressed pawl '48 that is screwed on the web 2. The hand lever I9 is journaled on a reduced rearward extension of ratchet wheel 20 for manual oscillation there- .about to cause pawl 4! to actuate wheel 20.

- Within the bore of the ratchet wheel are positioned two sets of annular metallic friction discs I00, IOI which are arranged in alternate sequence, the discs I00 having peripheral lugs I02 fitted into corresponding grooves I03 formed in ratchet wheel 20, and the discs IOI having lugs I04 on their inner circumferences fitted into corresponding grooves I05 formed in the stem of tensioning hub H. A series of flat, annular washers I05 are interposed between the discs I00, IN and between the discs and the hub 21 and cup 24,- which washers may be composed of fibre, leather, or other suitable material, and serve to cushion and render more efficient the action of the discs.

A short but strong expansion coil spring I0! is set in the cup 24 and is held in position by a nut I08 whichis' threaded on the extremity of stem 25 and is provided with recesses I09 for turning by afspanner; Thus the discs and washers are compressedfbetWeen the hub 2i and the cup 24,

4 and the degree of compression and, hence, the degree of frictional contact between the discs and washers, may be increased or decreased by screwing the nut I08 inwardly or outwardly to vary the pressure of the cup on the discs.

As a result of the arrangement hereinabove escribed, manual reciprocation of the lever I9 will rotate the ratchet wheel 20 and the discs I00 which are engaged therewith, while the frictional contact of the latter, through the washers I06, will likewise rotate the discs ml and the stem 25 with which the discs IOI are engaged, whereby the tensioning hub 2 I, which is integral with stem 25, will be functionally actuated.

It is customary practice for the operator to pass the wire strap loosely around the package to be bound and lead the free end 0 through the coil B. Thereupo-n, the tool is placed upon the package and moved at first laterally until its operative parts are correctly in line with the strap, and then to the left (Fig. 2) until the coil B abuts a stop 49 to insure that the coil and end of the strap to be severed are exactly in place for the crushing or knotting and severing, as is more fully described in the above named Patent No. 2,124,991. The free end C is then passed through the hook 31 and between teeth 46 on the hub 2I, to bring the parts to the position shown in Fig. 2 in readiness for tensioning of the strap.

The lever I9 is then raised to cause the jaw 5 to grip the body A of the strap, as explained in the above mentioned patent, following which the operator reciprocates the said lever and the resultant rotation of the hub 2| gradually increases the tension or tightness of the strap around the package, which procedure continues until the degree of tension equals or slightly exceeds the degree of frictional resistance to relative movement of the discs I00 with respect to the discs IOI. At

this point, the discs I09 which are engaged with the ratchet wheel 29 begin to slip and fail to drive the discs l0i which are engaged with the stem 25 of the hub 21, so that the latter ceases to rotate and further reciprocation of the lever I9 has no effect upon the tension of the strap. The operator at once senses this condition, brings the lever iii to its at rest position, shown in Fig. 2, and proceeds to actuate other parts of the too-1 for the purpose of knotting the strap and severing its excess extremity, all of which is described in said Patent 2,124,991, and will not be detailed herein as it constitutes no part of the present invention.

Important considerations relative to attainment of the best effect in binding and reinforcing packages with these straps include the proper strength of the knot formed by crushing the coil of the strap, and the proper tension of the strap when knotted. The mechanism above set forth achieves a remarkable advance in the perfection of the tensioning function, because the frictional resistance of the discs I00, IOI can be predetermined and fixed by the degree to which the nut I08 is caused to bear upon the cup 24 and, once this has been fixed, the successive straps will all receive the same tensioning regardless of variations in skill, physical strength, care, fatigue, etc. of the same or different operators. In other words, the human equation is practically eliminated and the desired tension is uniformly attained without danger of damaging the package or rupturing the strap. It should also be noted that, when the predetermined tension has been reached and the discs I00, IOI begin to slip, the operator can move the lever 19 to its at rest position without increasingthe tension 'on the strap, regardless of the position-of the lever at the moment.

Whilethe desiredpredetermined degree of frictional'resistance of the discs I60, 'IGI is initially obtained by direct pressure of the nut I08 on the cup 24;which latter bears directly on the discs,

the spring -Il is functionally-valuable because it compensates for'slight wear of the discsand'their washers 106 by forcing thenut I08 outwardlyand causing the 'hub 2I to compress the discs and washers together, thus maintaining constant their originally established-resistance.

Y In themcdified form of the invention shown in 'Fig. "5, the discs I00, IGI and their washers Hi2 "are substituted by -a bored truncated cone IIt which'is 'fitted on th'e' stem 250i the hub 2| and 'slidably fixed thereto by a key III; while the bore'ofratchet wheel 26 is tapered to receive the 'cone'I I0. 'Awasher I I2,of fibre or other suitable materiaL is inserted between the hub 2| andthe ratchet-wheel 20'.

The operative frictional-resistance is obtained inthis'form-ofthe invention by the contact between-cone III] and the correspondingly tapered bore-ofratchet wheel 20; the nut I88 and-spring I61 function "as in the form of the invention shown-inFig. 3; and the tool is handled and operatedas previously, described.

The second 'modified form of the invention shown in Fig.6, has a pair of bored truncated cones H3, H4 in-place of cone IIIl, which cones H3, 1 I dare slidably fined to the stem 25 of the hub 2 I by a key I I5; and the bore of the ratchet wheel 29 is reversely tapered to conform to the cones -II3,-I I4. Here the frictional resistance is derived from the contact of the cones with the ratchet wheel, while the associated parts act'as hereinbefore"described.

With reference to the third modified form of the invention shown in Figs. 7, 8 and 9, the construction, arrangement and operation of the tensioning hub 2 I and associated parts is as set forth in the previously named U. S. Patent application Serial Number 576,054, and the functional benefits'of-the present invention result from the construction and operation of the lever I9, which is here'composed of two parts H6, H1, which are pivotally connected, as indicated at I I8.

Lugs H9, I20, are formed integrally with the parts II6,I II respectively, and the said lugs are perforated to receive eye lts I2I, I22, which havetheir shanks threade for cooperation with nuts I23-and I24, that serve to adjust the bolts in the-lugs. A powerful retractile coil spring I25 has its ends bent in hook form for engagement with the eye bolts IZI, I22; the tension of the spring urging the parts H6, II! of the lever to the position shown in Fig. 7, and against move ment about the pivot I I8 to the position shown in Fig. 8. A shield or guard I26 is secured to the lever part II! by bolts I21 to protect the spring I 25 and the operator.

' In the use of this form of the invention, the nuts I23 and/or I24 are adjusted to impart to the spring I25 the desired resistanceto movement of'the lever part III about pivot H8. The lever I9'is then reciprocated to rotate the hub 2i and tension the strap, as previously explained, and, when the predetermined tension has been reached, the spring I25 will yield and permit the lever part II'I'to move on the pivot H3 from the position shown in Fig. '7 to or toward the position shown in Fig. 8, or beyond the last named position.

This will terminate the rotative efiect of' the lever I9 upon theme-21, and the operatcr will become aware th-at the predetermined tensioning of the strap hasbeen attained so that he may proceed to the activation of other I elements of the tool for knotting the strap andservi ng its excess end. 1

It will be seen that this invention providesfcr accomplishment-of package strapping"-with-nniformity in tension of the straps, according to predetermined standard, regardless ofvariations in any or all factors that contribute -to the operation of the tool;-a's a-result of which roper reinforcement of the packages is insured and' 'breakage o'f-straps and injury' to packages is eliminated or, at least, greatly minimized.

It will also be understood'that' various-changes maybe resorted to'in theform, "constr.uction and arrangement of the-part's-W'ithout departing from the spirit'and scope of the invention; and hence I do not intend "to be limited to details herein shown or described except asth'eymay be in cluded in the claims or required b'y-disclosures of the prior art.

What I claim is:

1 In a tool of thecharacter described,m'eehanism for tensioning a strap around aapackage, said mechanism including a rotatable-element for engaging and pulling the strap, a-stem -projecting co-axially from said element, operable rotating means surrcunding s'aid stem for imparting' -rotation tosaid element, and means intermediate said stem and said rotating means for causing-opera-' tion of the latter to rotate said element until' 'the tension of the strap resulting from the pulling of said. element thereupon reaches -a predetermin'ed degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprisingat leastone friction clutch member surrounding and engaged with said stem, at least one other friction clutch member surrounding said stem and-en gaged with'the rotating means, and means on said stem for holding said clutch 'membersin' frictional contact.

2. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap,'a stem projecting co-axially from said element, operable rotating means surrounding said stem'for' impart ing rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of thestrap resultingfrom clutch members in frictional contact, and yielding means on said stem for maintaining'said frictional contact by taking up wear between said members.

' 3. In a tool of thecharacter described, mechanism for tensioning-a strap-around a package, said mechanism including a rotatable element for engaging and pulling the strap,'a stem..pro-' jecting co-axially from said element, operable rotating means surrounding said stem for im-' partingrotation .to said element, vandmeanslintermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one friction clutch member surrounding and engaged with said stem, at least one other friction clutch member surrounding said stem and engaged witlr the rotating means, positively acting means on said stem for holding the said clutch members in frictional contact, and yielding means on said stem for maintaining said friction contact by taking up wear between said members, said means for holding the said clutch members in frictional contact and taking up wear therebetween including a nut threaded on said stem, a rigid element interposed between and in contact with said nut and a said clutch member and a resilient element in terposed between said nut and said rigid element.

4. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one friction clutch member surrounding and engaged with said stem, at least one other friction clutch member surrounding said stem and engaged with th rotating means, positively acting means on said stem for holding the said clutch members in frictional contact, and yieldirg means on said stem for maintaining said frictional contact by taking up wear between said members, said means for holding the said clutch members in frictional contact and taking up Wear I.

therebetween including a nut threaded on said stem, a rigid cup-shaped element interposed between and in contact with said nut and a said clutch member and an expansion spring housed in said cup-shaped element and bearing against it and said nut.

5. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degre while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one friction clutch disc surrounding and engaged with said stem, at least one other friction clutch disc surrounding said stem and en-- gaged with the rotating means, and means on said stem for holding said clutch members in frictional contact.

6. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one friction clutch disc surrounding and engaged with said stem, at least one other friction clutch disc surrounding said stem and engaged with the rotating means, positively acting means on said stem for holding the said clutch members in frictional contact, and yielding means on said stem for maintaining said frictional contact by taking up wear between said members.

7. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one conical clutch member surrounding and engaged with said stem, at least one other conical clutch member surrounding said stem and engaged with the rotating means, and means on said stem for holding said clutch members in frictional contact.

8. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising at least one conical clut member surrounding and engaged with said stem, at least one other conical clutch member surrounding said stem and engaged with the rotating means, positively acting means on said stem for holding the said clutch members in frictional contact, and yielding means on said stem for maintaining said frictional contact by taking up wear between said members.

9. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective there after, said intermediate means comprising a plurality of conical clutch members surrounding and engaged with said stem, a complementarily shaped clutch member surrounding said stem and engaged with the rotating means, and means on said stem for holding said clutch members in frictional contact.

10. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising a plurality of conical clutch members surrounding and engaged with said stem, 3. complementarily shaped clutch member surrounding said stem and engaged with the rotating means,

positively acting means on said stem for holding the said clutch members in frictional contact, and yielding means on said stem for maintaining said frictional contact by taking up wear between said members.

11. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising a plurality of oppositely tapered conical clutch members surrounding and engaged with said stem, a complementarily shaped clutch member surrounding said stem and engaged with the rotating means, and means on said stem for holding said clutch members in frictional con tact.

12. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, operable rotating means surrounding said stem for imparting rotation to said element, and means intermediate said stem and said rotating means for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said rotating means to become ineffective thereafter, said intermediate means comprising a plurality of oppositely tapered conical clutch members surrounding and engaged with said stem, a complementarily shaped clutch member surrounding said stem and engaged with the rotating means, positively acting means on said stem for holding the said clutch members in frictional contact, and yielding means on said stem for maintaining said frictional contact by taking up wear between said members.

13. In a tool of the character described, mechanism for tensioning a strap around a package,

ISO

said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, a bored rotatable ratchet surrounding said stem for imparting rotation to said element, and means within the bore of said ratchet for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said ratchet to become inelfective thereafter, said last named means comprising at least one friction clutch member surrounding and engaged with said stem, at least one other friction clutch member engaged with the bore of said ratchet, and means for holding said clutch members in frictional contact.

14. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, a conically bored rotatable ratchet surrounding said stem for imparting rotation to said element, and means within the bore of said ratchet for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said ratchet to become ineffective thereafter, said last named means comprising at least one conical clutch member surrounding and engaged with said stem, and means for holding said clutch member in frictional contact with the bore of the ratchet.

15. In a tool of the character described, mechanism for tensioning a strap around a package, said mechanism including a rotatable element for engaging and pulling the strap, a stem projecting co-axially from said element, a reversely conically bored rotatable ratchet surrounding said stem for imparting rotation to said element, and means within the bore of said ratchet for causing operation of the latter to rotate said element until the tension of the strap resulting from the pulling of said element thereupon reaches a predetermined degree while permitting the operation of said ratchet to become ineffective thereafter, said last named means comprising a pair of oppositely tapered conical clutch members surrounding and engaged with said stem, and means for holding said clutch members in frictional contact with the bore of the ratchet.

HAROLD K. EMBREE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,217,746 Graf Feb. 2'7, 1917 1,486,354 Mueller Mar. 11, 1924 2,002,115 Kjaer May 21, 1935 2,007,002 Porter July 2, 1935 2,124,991 Watt et al. July 26, 1938 2,204,572 Childress June 18, 1940 2,229,786 Abbott Jan. 28, 1941 2,296,175 Morkoski Sept. 15, 1942 2,333,980 Branson Nov. 9, 1943 FOREIGN PATENTS Number Country Date 126,505 Great Britain May 15, 1919 

